Locking means for the doors of elevators



Dec. 8, 1931.

H. C. WERNER LOCKING MEANS FOR THE DOORS OF ELEVATORS a Sheets-Sheet 1 Filed Sept. 27, 1928 PPM cmfl Wm \NVENTOR BY "a IM'IW ATTORNEY Dec. 8, 1931 H. c. 'WERNER LOCKHEG MEANS FOR THE DOORS OF ELEVATORS 27, 1928 3 Sheets-Sheet 2 Filed Sept.

V V 1 v 9. V l H 1 4 m m M W M Y E N R O W A Dec. 8 1931.

H. o WERNER 1,835,544

LOOKING MEANS FOR THE DOORS OF ELEVATORS 3 Sheets-Sheet 3 Filed Sept. 27, 1928' HWCw-i W INVENTOR ,v "wan Patented Dec. 8, 1931 UNITED STATES PATENT OFFlCE.

HERMAN CARL WERNER, OF CROYDON, NEAR SYDNEY, NEW SOUTH ALES, AUSTRALIA, ASSIGN-OR TO- OTIS ELEVATOR. COMPANY, OF NEW YORK, N. Y.

LOCKING MEANS FOR THE DOORS 0F ELEVATORS Application filed September 27, 1928, Serial No.

This invention has been devised with the object of assuring better safety in the operation of elevators by providing means in the door locking arrangements for interlocking mechanical fastening elements with the electric circuit control elements in such a way that eiiectivemechanical locking must be es tablished before the electrical controls can operate. In the absence of interlocking means operating in that way, the electric control circuits may be closedand the car put in motion when the landing door is not eflectively locked, notwithstanding that the door has been brought to the closed position, and a danger condition then exists as the'unsecured door may be opened inadvertently whilst the elevator is in motion or whilst it is at rest at any position in the elevator well. The defect which the present invention is'aimed to avoid results from the fact that the known mechanical door locking means depend on grav ity or spring action for engagement of a hook latch or the equivalent member of the latch assembly on the door with a staple fixed on the well enclosure, whilst closure of the electric circuit connections depends upon movement of another element by contact with that element of the landing door or of a member which is carried by the landing door. If the latch hook or other fastener fails to engage the staple, the door, though it may be at the closed position, is still free to be opened. The improved arrangement now proposed ensures that effective mechanical locking of the landing door must take place before the electric circuits which control the elevator car movement can be completed.

It is entirely practicable to connect the landing door latch locking equipment and the car door latch equipment in series so as thereby to obtain a security of closure of both doors as a condition precedent to the operation of the elevator; but in practice it would rarely if ever be necessary to'fit the control arrangements in which the present invention consists on the elevator 'car door; it would only be necessary to protect the landing doors except where official regulations re quire an electrical I contact to be associated with the car door in such a way that the con- 308,839, and in Australia September 29, 1927.

ngs in the practical arrangement in which it is applied for ensuring the efi'ective closing and locking of the landing doors to enable operation of the elevator. Two forms of the device are illustrated in the accompanying drawings, one of these forms in Figs. 1 and 2, and the other in Figs. 3 and 4:. The principle is identical in both cases, the distinction between them being that in the Fig. 3-4 arrangement three additional contacts are provided in-series in the circuit with a closing arrangement which is controlled by the latch so that in the event of breakage of the latch jaw the circuit will be interrupted notwithstanding that the door position has not been disturbed.

Fig 1 is an interior elevational view of the latch box and the staple box and the mechanism therein, as theyappear wh'enthe landing door is closed, and locked and the releasing cam is raised or withdrawn to permit engagement of the'locking elements; and Fig. 2 is a similar view (omitting some of the parts in the staple box) as the parts appear when the releasing cam is dropped and the mechanical locking means are released and the door is open. These views represent the simpler form of the arrangement in which two contacts are interposed serially in the control circuit; one of these contacts is made when a stud on the door is brought against a spring blade in the staple box when the door comes to the full closed position; the other contact is made with a stud on the latch case, by a spring blade which is carried on a part of the mechanical lock in the stapler The mechanical lock cannot check the latch hook or engage the security hook unless the latch hook as first effectively engaged the staple, and it then operates not only to check the latch hook but also to. engage the security hook whichis fixed on the latch case, thus to 7 provide a double mechanical lock to prevent opening of the door.

r Fig. 3 is an interior elevational view of the latch box and the staple box and'the stalled on the elevator car 10.

hook closing spring.

mechanism therein, as they appear when the landing door is closed and locked and the releasing cam has been raised or with drawn; and Fig. 4 is a similar view (omitting some of the parts in the staple box), as the parts appear when the door is open. These views represent an arrangement in which five contacts are interposed in the control circuit and provision is made for preventing access of the fingers to an electrically live member through the ap-- ertures in the staple box. In essence, the arrangement differs from that shown in Figs. 1 and 2 only in effect that three additional breaks in the control circuit are provided.

Fig. 5 is a diagrammatic view showing the usual releasing cam equipment on an elevator car;

Fig. 6 is an incomplete diagram for an automatic electric lift;

Fig. 7 is a frontal elevational view of the controller handpiece of an electrically operated lift and its dial fitted with coacting con tact studs; and

Fig. 8 is a semi-diagrammatic fragmenta'ry view explanatory of a device which is provided for stopping the operating rope in elevators equipped with rope control.

There is no novelty disclosed in Figs. 5 to 8, and those figures are provided only to facilitate explanation of the operation of the devices which are illustratedin Figs. 1' and 2 and Figs. 3 and 4 respectively.

In Fig. 5, 10 is the elevator car, 11 the landing level, 12 the landing door, 13'the' staple box which is fixed on the'qwell enclosure, 14 the latch box which is fixed on the landing door 12, 15 the releaser cam, 16 the releaser cam carrier links, 17 the-striker arm of the staple assembly which 'coacts with the cam 15, 18 the pull line which connects the cam 15 to the cam motor or solenoid 19 which is in In Fig. 6, 20 are the landing call buttons, 21 the control buttons in the car paralleled with the landing call buttons 20, 22 the car holding relay, 23 electro-magnetic floor switches, and 24 their contacts, 25 a solenoid which operates a shnntin switch 26 through which current reaches the retiring cam operating device 19, 27 car direction automatic switches, 28- the door contacts arranged in seriesin the operating line. 19 is the cam operating device and 29 are the floor level elevator car stopping switches.

' Referring to Figs. 1 and 2-35 is the main ually operated latch lift finger lever in the latch box, 36 the latch hook, and 37 the latch 38 is a security hook which is fixed on the faceof the latch box 39. 40 and 41 are contact makin studs which are fixed on but electrically insulated from the face of the latch box. is a conductive bridge connecting the'studs 40 and 41. The latch box 39 is fixed to thelanding door. 43

is the staple box; it is fixed to the lift well enclosure in operative relation to the latch box 39, and has three apertures 44, 45 and 46 in its face to accommodate the latch hook 36, the security hook 38 and the contact stud 41, and the contact stud 40 respectively. 47 is the outgoing end of the control circuit line which is connected to a spring contact finger 48 which is touched by the button 40 when the landing door is closed, 48a: being an insulated carrier block, 49 is a tumbler which swings about a pivot 50 and is shaped to engage the security hook 38, 51 is a striker arm connected to the tumbler 49 and fitted with a spring finger mounted on the block 53 in operative relation to the contact stud 41, 55 a flexible conductor from the finger 54 to the incoming end 56 of the control line, 58 a link connecting the tumbler 49 to the latch check 59, and a spring which forces the latch check 59 and the tumbler 49 to the closed position. 57 is an auxiliary spring having the same function. Gravity assists the springs 57 and 60 to close the locking elements. The latch check 59 is centered on a pivot stud 61.

The operation is as follows Assuming that the landing door is open, the latch and staple mechanisms are in the position shown in Fig. 2 except that the latch 36 Will be down'in the drawings it is shown in lifted position. hen the door is closed, the latch hook 36 strikes over the staple lip 62., the security hook 88 passes into the staple box through the aperture 45, and the contact stud 40 passes into the staple box through the aperture 46. The stud 40, when full in, makes contact with the spring plate 48. A ssuming that the latch hook 36 has dropped into the position. shown in Fig. 1, it then possible for the mechanical check and locking devices to operate, but unless it has dropped down to the Fig. 1 position those mechanical devices cannot operate, and the electric control circuit cannot therefore be completed. When the control switch has been moved from. centre to close one or other of the driving contacts, or when a control button has been pressed or equivalent operative means have been actuated manually the releasing cam 15 is lifted and the pressure against the striker arm 51 which held the mechanical parts at open position and also held the circuit contacts at open position, as shown in Fig. 2, is thus relieved. The springs 60 and 57 and the gravity effect of the locking mechanism then moves that mechanism to the locked position which is shown in Fig. 1. At that position one of the steps on the check piece 59 engages above the latch hook 36, and effectively holds the latch hook so that it cannot be lifted out of the staple. As long as it is thus held the door will be secured. The'tumbler 49, however, provides another more important locking means. Theclaw end of the tumbler engages the security hook 38. It cannot engage the security hook unless thedoor is at the full closed position. There is thus a double insurance against the closing of the mechanical devices, as before they can be closed the security hook 38 must be at the full-in position, and the latch hook 36 must also be at the latched position. lVhen the mechanical lock has been thus operated, the spring blade 54 has been brought into contact with'the button 41 which is exposed on the face of the latch box and projects into the aperture 45 when the landing door is at the closed position. When this contact 5441 has been made, a circuit iseflectively established from the line 47, through the blade 48, the stud 40, the bridge 42, the stud 41, the blade 54, and the flexible connector 55, to the line'56, and the elevator car may then be operated. If, however, either of the contacts at 48 01154 be incomplete, there will be no circuit from the line 47 to the line 56 and operation of the elevator car will be impossible, and, as has been explained. the contacts at 40 and 41 can only be established when the landing door has been fully closed, the latch 36 fully engaged with the staple, the latch check 59 brought into engagement with the latch hook 36, and the claw of the tumbler 49 engaged with the security hook 38. The security hook 38 thus provides a. lock independent of the latch 36, so that the landing door willbe held secure notwithstanding a failure in the latch hook 36, this hook being the element which is subject to mechanical wear and stress and therefore liable to failure.

Referring to Figs. 3 and 4: The arrangement is substantially identical with that already described, subject to a mechanical and electrical modification to provide for additional contacts in series in the line. The additional contacts which are provided are, a breaking contact to take the place of the flexible connection at 55, and contacts in series associated with a drop arm which is actuated by the latch hook 36. The tumbler 49 is in this case not mechanically connected to the drop arm 70 through which the additional contacts 7172 are operated. These contact members 7172 are spring blades and they are bridged by a plate 73 which is carried on an insulating block 74 which is fixed on the drop arm 70. 75 is a resting stud to limit the drop of the arm 70. The arm 70 is freely pivoted at 76 in the staple case 43; it is actuated by the latch hook 36 when the door is being closed home; the latch hook 36 engages behind the staple lip 77 in an upward movement. The tumbler 49 when disengaged is at its back position,

I as seen in Fig. 4 to clear the security hook38 -53 which is accommodated in shape for the purpose. The contact at 78 is opened posi tively in the backward movement of the tumbler 49, and good clearance is established be fore the tumbler claw releases its engagement with the security hook 38. The circuit is thus positively broken at 78 and also at 79- 80 before thesecurity hook 38 is mechanically released, and before the check which is imposed bythe top end of the tumbler 49 under the jaw of the latch hook 36 has been cleared. Consequently, the door cannot be moved until after the electrical circuits. have been positively broken. As soon as movement of the door takes place, the arm 70 drops by gravity, opening the contacts at 71-72, and the stud 40 moving back from the spring finger 48 breaks the circuit also at that point. The circuit is thus broken at five points in series, viz., at 48, 78 79, 7'1 and 72, certain of these breaks occurring in the initial part of the release movement of themechanical locking devices and the'other breaks taking place when the latch hook 36 is manually operated and the ddor then moved towards the open posi tion. The diiferent arrangement of the closing springs associated with the latch is quite immaterial. The latch used in the arrange- 'n'ient shown in F1'gs.'3 and 4 1s a direct acting-latch,whereas the latch shown in Figs. 1 and 2 is an indirect latch, but it is immaterial whether the hand piece and the latch claw are members.

The essential feature of novelty in the invention is the provision of means whereby the mereclosing of the door is in itself inoperative for establishing the operating circuits for 1?."

blockage of the mechanism through the acci- 1;"

dental intrusion of something into the staple case, or through mechanical failure of some part of the mechanism. In such cases a positive danger exists, as the operating circuit being established consequent upon the door being closed but not necessarily mechanically securechtheelevator car may be moved and the landing door left in 'an unprotected conconstructed as one member or as associated 1* dition, softhat it may be opened inadvertently whilst the car is not stationary at the "for the elevator is broadly novel.

It will be understood that the conventional retiring cam arrangement isnot necessary to the operation of the system ofcontrol which is described with reference to Figs. 1 to 4.

For the conventional retiring cam any other device ofan equivalent nature may be substituted which operates to move an element in the staple locking equipment when the control device, whether it be a rope or switch or button or other means is operated to bring the elevator car into motion.

referring to Fig. 8, 80 is the operating rope such as is used forthe control of hydraulic driven elevators. 81 is a stopper through. which tne rope 80 runs, 82 is a grip shoe associated with the stopper 81; this grip shoe is forced home to bind the rope80 and prevent the operator from moving the rope to bring the car into motion. This locking movement is ell ected by a spring 83 and the retiring movement of the gripper 82 is effected by an electrormagnet 84. This magnet is in the operating circuit -l7-56 (refer to Figs. 1 to l). lVhen that circuit is broken, the spring 83 is operative and-the rope 80 is held. The magnet 84s is energized only when the control circuit is completed through the effective operation of the latch and lock mechanism which described with reference to Figs. 1 to ll Tll'.1'CSlllt'lS that the elevator car cannot be brought into motion until a safe condition has been established at all landing doors in the installation.-

The disposition of the contact making devices is such that an accidental shorting across any two or more ofthem is so remote to be entirely negligi ale. This observa; tion applies particularly to the contacts l854-.

'What I claim as my invention and desire to secure by Letters Patent is a 1. Locking mechanism for an elevator door comprising, a staple, a catch'inember in said staple, a lock member carried by said door and cooperating with said catch member when the door is closed to lock said door, a. manually releasable latch hook carried by the door and cooperating with said staple to latch said door in closed position, and means for preventing the release ofsaid latch. hook so long as said door is locked by said catch member and said lock member.

2. Interlocking mechanism for an elevator door comprising, a staple. a catch memher in said staple, a member carried by said door and cooperating with said catch memier when the door is closed to lock said door, manually releasable latch hook carried by the door and cooperating with said staple to latch said door in closed position, circuit controlling means controlled by said catch member and closed when the door is locked by the cooperation of said catch member and said member carried by the door, and means operatively connected to said catch member for preventing the release of said latch hook to unlatch'the door prior to the opening of said circuit controlling means by said catch member.

Locking mechanismi or an elevator door comprising, a staple, acatchmeniber pivotally mounted in said staple, a hook carried. by

said door and engageable by said catch. member when said door is closed to lock said door, a latch hook carried by said door and independent of the first mentioned hook, said latch hook cooperating with a wall of said staple to latchsaid door in closed position,

catch member when said door is closed to lock said door, said catch member e. Lending into the path of movement of said book, a latch hook carried by said door and independent of the first mentioned hook, said latch hook cooperating with a wall of said staple to latch said door in closed position.

means for manually releasing said latch hook, and a check member pivot ally mounts; in said staple and connected to said catch member, said check member being operable by said latch hookinthe closing movement of said door to enforce retirement of said catch member tromthe path of movement of said first mentioned jhook.

5. Locking mech anism for an ele *ator door comprising, a staple, catch member pivotally' mounted in said staple. hook carried by said door and engageable by said catch member "when said door is closed to lock said door, said catch n'rmber extending into the path of movement of said hook, a latch hook carried by said door and independent of the first mentioned hook, said latch hook cooperating with a wall of said staple to latch said door closed position, means for manually releasing said latch hook, and a check member pivotally mounted in, said staple and operably connected to said catch member, said check member being operable by said latch hook in the c g movement of said door to enforce retirement of said catch member from the path of movement of said lock member and oper able upon the engagement of d latch hook with said casing s .lland the lOcll up; or Mud door by said catch'member and said ii so mentioned hook-to lock said latch hook in latching engagement with said staple wall.

. 6. Locking mechanism for an elevator door comprising, a staple, a catch member pivotally mounted in said staple, a hook carried by said door and engageable by said catch member when said door is closed to lock said door, a latch hook carried by said door andindependent of the first mentioned hook, said latch hook cooperating with a wall of said staple to latch said door in closed position, means for manually releasing said latch hook, a check member pivotally mounted in said staple and operably connected to said catch member, said check member being operable upon the engagement of said latch hook with said casing wall and the locking of said door by said catch member and said first mentioned hook to lock said latch hook in latching engagement with said staple wall, and means forreleasing said catch member from said first mentioned hook and said check member from said latch hook when said door is closed to unlock said door and permit the release of said latch hook from the staple wall.

7. Interlock mechanism for an elevator door comprising, a pair of connected contacts carried by the door, a lock member carried by the door, a fixed contact engageable by one of said pair of contacts when the door is closed, a catch member for engaging said lock member when the door is closed to lock said door, and a contact carried by said catch member for engaging the other of said pairs of contacts only when the door is fully closed and locked by the engagement of said catch member with said lock member.

8. Interlocking mechanism for an elevator doorcomprising,astaple,a catch member pivotally mounted in said staple, a hook carried by said door and engageable by said catch member when said door is closed to lock said door, a latch hook carried by said door and independent or" the first mentioned hook, said latch hook cooperating with a wall of said staple to latch said door in closed position, means for manually releasing said latch hook, circuit controlling means closed when said door is closed, additional circuit controlling means, and means for preventing the closure of said additional circuit controlling means until said door is latched by said cooperation of said latch hook with said staple wall and locked by the cooperation of said catch memher and said first mentioned hook.

9. Interlocking mechanism for an elevator door comprising, a staple, a catch member pivotally mounted in said staple, a hook carried by said door and engageable by said catch member when said door is closed to lock said door, a latch hook carried by said door and independent of the first mentioned hook, said latch hook cooperating with a wall of said staple to latch said door in closed position, means for manually releasing said latch hook, circuit controlling means closed when said door is closed, additional circuit controlling means, and means for preventing the locking of the door by said catch member and said first mentioned hook and the closure of said additional circuit controlling means until said door is latched by said cooperation of said latch hook and staple wall.

10. Interlocking mechanism for an elevator door comprising, a staple, a catch member pivotally mounted in said staple, a hook can ried by said door and engageable by said catch member when said door is closed to lock said door, a latch hook carried by said door and independent of the first mentioned hook, said latch hook cooperating with a wall of said staple to latch said door in closed position, means for manually releasing said latch hook, circuit controlling means closed when said door is closed, additional circuit controlling means, means for preventing the locl ing of the door by said catch member and said firstmentioned hook until said door is latch-ed by said cooperation of said latch hook and staple wall, and means for preventing the closure of said additional circuit controlling means until said door is locked by said catch member and said first mentioned hook.

In testimony whereof I alfix my signature.

HERMAN CARL WERNER. 

